In the emergency transportation of patients from an area at which they become ill to a primary treatment source, such as a hospital, time is frequently of the essence. Although the art of transport of such emergency victims and patients has progressed to the state where many communities have paramedics and paramedical-type vehicles manned by trained technicians and equipped for communication with the hospital to which the patient is being transported; frequently the necessity to quickly transport the patient means that the patient is being given fluids by means of a catheter with needed medications during transport.
This can present a very difficult situation for the paramedic or technician who is inserting the catheter and hazards to the patient not the least of which is the risk of introducing an air embolism into the venous and/or arterial system of the patient, which can be fatal. Under such circumstances of transport, it is customary for the paramedic or technician to receive instructions as to what I.V. material(s) the patient is to be given based on the communication of vital signs and changes in vital signs, such as blood pressure, temperature, pulse, respiration, etc.
Similarly it is not unusual under these circumstances for difficulty to be encountered in inserting the catheter needle during venipuncture, and frequently several or more such venipuncture attempts are required before satisfactory venipuncture is obtained while the technician is doing his best to avoid introducing air into the patient's veins. Not only do these activities present difficulties with regard to the handling of the patient, but it is intimidating to the technician during the transport.
After inserting the cannula and removing the stylet (needle), the tubing leading from the I.V. bottle is coupled to the catheter. It is during this coupling that potential air can be trapped in the tubing and when the clamp is released on the tubing, air can be pushed by the incoming fluids forcing the air in the tubing to enter the patient. A potential fatal embolus could then occur. The device of this invention allows this trapped air to be vented in the catheter reducing the risk of air embolism.
Various solutions to the foregoing problems have been proposed in varying ways in different patents. For example, U.S. Pat. No. 4,417,886 issued to Paul L. Frankhouser, et al. contains a guide tube extending rearwardly from the hub on the back of the catheter needle. A wire guide is mounted in the tube with a wire guide actuating handle projecting through an elongated slot in the side wall of the tubing. The introducer assembly for such catheter is contained in a sterile package and removed as an entire unit including needle, catheter, wire guide and wire guide feed device. Such catheter introduction set is intended for use in placing I.V. lines into small vessels such as the radial artery of a patient. The wire guide has a handle which is adapted to advance a spring wire guide through the lumen of the needle and outwardly from the distal end into and through the lumen of the blood vessel into which the I.V. line is being placed.
U.S. Pat. No. 4,389,210, issued to Joseph N. Genese, includes a spliced two-part needle and a catheter unit comprising a catheter, winged catheter insertion means, flexible tubing and a tube hub, wherein axial and rotational alignment of the needle and catheter unit are maintained by mechanically interlocked complimentary portions of the needle and lumen of the winged catheter insertion means. After venipuncture has been achieved and the catheter has been fully inserted into the vein, the wings are then taped to the patient in accordance with the conventional techniques for so doing.
U.S. Pat. No. 4,193,399, issued to Thomas P. Robinson, discloses a self-venting plug for a venous entry unit which is a porous plastic body adapted to be removably seated in a hollow flashback chamber. The plug comprises an open pored plastic having a pore size on the order of 10 to 15 microns, and provides a flow path for venting air from the flashback chamber while inhibiting flow of blood from the chamber. The plug may be used, for example, with over-the-needle and through-the-needle catheter units employing piercing needles, and may be used to anchor a stylet for stiffening a catheter to be forwarded into the body.
U.S. Pat. No. 3,714,945, issued to Vayden F. Stanley, is directed to an over-the-needle catheter insertion device wherein the catheter and needle are connected to respective interconnecting hub members. The catheter hub member is connectable to an infusion source for an I.V. fluid. The catheter hub member has an outwardly extending ridge molded integrally therewith, providing a means by which the catheter hub and needle hub can be separated by manipulation by only one hand. This separating means is disclosed as being operable by digit flexure of the operator's thumb leaving the technician's other hand free to apply pressure in the area of the venipuncture in order to prevent blood flow through the catheter. Alternatively, the thumb or thumbnail can engage the rearward portion or bib of the catheter hub to remove the needle hub and the needle.
U.S. Pat. No. 3,721,231, issued to Franz Hans Hubert, is directed to a medical catheter formed from a hub from within which an elongated flexible tube is disposed. The bore of the tubing within the hub is tapered to accept the tapered tip of a male connector. The tubing is coextensive with the shaft of the hub. There is also disclosed a method for fabricating the catheter involving mounting the hub on a mandrel which has a tapered portion, adapted to be positioned within the hub, and an elongated pilot extending from the tapered portion through the hub. Heat softenable catheter tubing is fed onto the tapered portion until resistance is met, then the tubing while heat softened, is forced over the tapered portion of the mandrel in the recess between the tapered portion and the hub. The tubing is solidified and the joined catheter removed from the mandrel. The Hubert invention is directed to a medical catheter particularly suitable for high pressure applications, such as high pressure angiocardiography injection machines where an internal pressure in the order of 1,100 pounds per square inch is developed within the hub and the catheter.
U.S. Pat. No. 3,589,361, issued to Douglas A. Loper, is directed to an intravenous catheter, of the needle-inside type, having a wing assembly serving to guide the catheter and needle during venipuncture and adapted to hold the catheter firmly in place after venipuncture. The design of the Loper catheter wings enables the technician to grasp the wings during venipuncture permitting use of the wings to guide the needle and thus the I.V. tubing passing there through. The bottom portion of the wings can have pressure sensitive adhesive applied directly thereto in order to adhesively attach the catheter to the patient's body thereby holding it in place.
It will be observed that the improved winged catheter device of the present invention has several advantages over that of Loper. According to the present invention, the structure of the wing portions of the catheter is such that an air breathing foam lies intermediate between the flexible plastic wings and the pressure sensitive adhesive which is in contact with the patient's skin. A release layer, which can be paper or plastic material, is in contact with the adhesive and upon removal thereof the adhesive then contacts the patient's skin for immobilization of the position of the catheter after venipuncture and placement of the I.V. tubing have been obtained. Moreover, in accordance with one embodiment of this invention, the central housing portion of the catheter unit has molded integrally therewith a grooved or slotted wing portion for holding the I.V. tubing in place. Alternatively, one or both of the I.V. wings can have clips or other tubing-retaining members molded on the supper surface(s) thereof to provide for positioning of the I.V. tubing between its intravenous position and the I.V. bag or bottle from which the intravenous fluid is administered to the patient.